I was told that pipe is often welded seam, while tubing is extruded as one,
with no welds
"Harold & Susan Vordos" wrote in message
...

"Yvan" wrote in message
news
What is the difference? I have purchased manual for building mini chopper
frame, and I have no idea what to ask for in shop (where I am no one in
metal shop - or any other speaks English). English is not my native
language, so please go easy.

Pipe is measured by it's internal diameter, and is not usually very
precise.
Regardless of the schedule, the outside diameter remains constant (at
least
in theory). When the schedule of the pipe changes, the wall gets thicker
or thinner, so the size of the hole in the pipe changes.

That rule applies to pipe up to 12". Once pipe goes above that size, it
is
measured by the actual outside diameter, meaning 14" pipe OD measures 14",
unlike 12" pipe, which measures 12-3/4".

Tubing is measured by the outside diameter. When you buy tubing, you
specify the wall thickness and the outside diameter. That would be the
equivalent of specifying schedule when buying pipe.

The advantage of tubing over pipe is that it is made in a much wider
variety
of sizes. Pipe is restricted, and the larger it gets, the larger is the
restriction. Still, each of them have a purpose that they serve well.

And what is the difference when bending pipe and bending tube. I knew
that
bending tools are different, but why? Something to do with a diameter?


I'm not well versed on pipe or tube bending, but they bend similar to one
another. Your comments on diameter are close to the problem-----if you
expect good bends. The shoes that support the material must be a proper
fit
to prevent kinking or otherwise distorting the material at hand while
bending. Perhaps someone with bending experience will chime in and
provide
more details.

Hope this helps

Harold


the tools used must fit the material at hand.